These are starter templates for bases.

I'm not a designer.This is just a starter template I use to make it easier to create my first base.

The core is in the middle, second layer down.

I have posted several versions of this using different materials. All of them are the same dimensions (17 X 4 x 17). Not a solid 4 deep but in several places to give plenty of support for more than 1 level if desired.